A phase II, multicenter, single-arm trial of eribulin in patients with bevacizumab-resistant recurrent glioblastoma.
Authors: Masamichi Takahashi, Satoshi Kawashima, Yohei Otake, Natsuko Satomi-Tsushita, Aya Kuchiba, Ryo Sadachi, Keiko Ohata, Hitoshi Ozawa, Kan Yonemori, Motoo Nagane, Yoshiki Arakawa, Akitake Mukasa, Shota Tanaka, Ryo Nishikawa, Yoshihiro Muragaki, Kenkichi Masutomi, Koichi Ichimura, Kenichi Nakamura, Yoshitaka Narita
Journal: Journal of Clinical Oncology (2022)

2036 Background: Glioblastoma (GBM) is one of the worst prognostic cancers and there is no effective treatment after failure of bevacizumab. Eribulin is a microtubule inhibitor used for the treatment of patients with metastatic breast cancer and liposarcoma. We previously reported that eribulin strongly inhibits the RNA-dependent RNA polymerase (RdRP) activity of TERT protein in cancer cells, and has a strong anti-tumor effect against GBM cells with TERT promoter mutation. In this study we aim to investigate the efficacy and safety of eribulin in patients with bevacizumab-resistant recurrent GBM. Methods: This is an open-label, multicenter, single-arm phase II trial. Eligible patients aged 20-75 years with bevacizumab-resistant recurrent GBM were enrolled from 2018-2020. Patients received eribulin 1.4 mg/m 2 on days 1 and 8 of 21-day cycle until disease progression or intolerable toxicity was observed. The primary endpoint was one-year overall survival rate (1yOS%). The 35 patients are needed to achieve an 80% power at a one-sided alpha of 10%, under threshold 1yOS% of 10% and expected 1yOS% of 25%. Results: Thirty-seven patients aged 26-73 (median: 54) years were treated. Twenty-six of 37 (70.3%) patients were diagnosed as IDH-wildtype GBM, 4 (10.8%) were with IDH-mutant GBM and 7 (18.9%) were GBM, NOS. Thirty-four (91.9%) patients had a Karnofsky performance status of 70 or 80 at the registration. Thirty-one (83.8%) patients received additional treatments, including 28 (75.7%) bevacizumab, 11 (29.7%) re-irradiation and 3 (8.1%) resection after failure of eribulin. Among 37 subjects, 32 surgical specimens were analyzed for TERT promoter mutation and 15 for RdRP activity. 1yOS% was 29.7% [80% CI: 20.5 to 39.5 (p &lt; 0.0001), 95% CI: 16.1 to 44.6]. Median OS was 9.0 months [95% CI: 6.2 to 11.0] and median progression-free survival was 1.5 months [95% CI: 1.4 to 1.7]. Neither TERT nor RdRP statuses was associated with prolonged OS. Among all the target lesions evaluated, two lesions decreased more than 50% in size and the patients survived more than one year, however no obvious PR was confirmed at the final evaluation. The disease control rate was 25.7% [95% CI: 12.5 to 43.3]. Common ≥ grade 2 AEs were neutropenia (70.3%), leukopenia (56.8%), lymphopenia (27.0%), elevation of γ-GTP (13.5%), elevation of ALT (10.8%), elevation of AST (8.1%), alopecia (8.1%). Treatment-related grade 3 or 4 AEs occurred in 59.5% of subjects. There were no AEs leading to death. Conclusions: Eribulin was safely applied for the patients with recurrent GBM. This phase II study met its primary endpoint of 1yOS%, although no obvious response was observed. Further investigation to reveal the biomarkers related to longer survival is underway. Clinical trial information: UMIN000030359.